Photographic film and compound support



PHOTOGRAPHIC -FILM AND COMPOUND SUPPORT.

FILED FEB.25,1921.

ATTORNEY Patented dan. 2, 1%23.

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STEW'ART TI. CARROLL,.OF ROCHESTER, NEW YORK, ASSGNOR TO EASTMAN KODAK COMPANY, OF ROCHESTER, NEW YORK, A CORPORATION 0F NEW YORK.

PHOTOGRAlHlC FILM AND COMPOUND ASUEPORT.

applicati@ inea February 25, 1921', serial Naarmate.

To all 107mm 'it may concern:

Be it known that I, VS'rEwAIrr Jj. CARROLL,

a citizen of the United States of America, y

residing at Rochester, in the county; of Monroe and State of New York, have invented certain newv and useful Impnevements in Photographic Film and Compound Supports, of which the following is a full,

' clear, and exact specification.

This invention relates' to a photographic film with a compound cellulosic sheet which is particularly adapted for use as a support in photographic film. The object of this linvention is to provide a film with a support having the usual qualities demanded by commercial.conditions in the photographic* art, which will also possess a diminished rate of burning, and will be so constituted that the markings due to electrical discharges (commonly called static) are prevented or very greatly minimized. Cther objects will hereinafter appeanj Ordinary photographic ilm, particularly suclr as is used in motion picture work, generally embodies a support'of nitrocellulose. As usually composed, this support has the essential qualities for commercial work. But I have found that it can be improved so as to diminish the fire risk .involved in Ahandling it and so as to minimize the possibilityl of static. These desirable effects have been able to accomplish by coating or varnishing both faces `of the nitrocellulose support with alayer of cellulose ether,'of the kind indicated in U. S. Patent No. 1,188,376, Lilienfeld, June 20, 1916. The compoundcellulosic support thus produced islinally coated with the gelatino-silver haloid emulsion or other suitable photographic layer. If this layer be one that is especially sensitive, `my compound base greatly minimizes the possibility of static.

is a sectional view on an exaggerated scale of a film embodying my invention.

The nitrocellulose support 1 carries on each face a cellulose ether layer 2, the sensitive layer 3 being carried on either ether layer 2.

By way of example, l may dissolve 100 parts of ethylcellulose in a compound solvent composed of 340 parts of benzol and lfl'Orparts of ethyl alcohol. Some acetone may also be added to promote adhesion, ifdesired, as indicatedin a copending application of Albert F. Sulzer,` Serial No. L

446.782, sied Feb.. 21, 1921.

This lm with its compound support is resistant to static, and the presence of slowburning ether on the surface of the nitrate appreciably slows down the rate of combustion of the latter, thus diminishing the fire risk.

Having thus described'my invention, what l claim as new and desire to secure by Letters Patent is:

1. A; photographic film having its sensitive layer carried on a compound support, .the lat-ter comprising a layer containing nitrocellulose bearing on eachface a layer containing a celluloseether.

2. A photographic ilm having its sensitive layer carried on a compound lm support, the latter comprising a layer containing nitrocelluloseA coated on bot-h faces with ethyl cellulose.

3. A compound support comprising a layer containing a cellulose ester bearing on each face a coatingcontaining a cellulose. ether. i

4. A compound support comprising a layer containing nitrocellulose coated on each face with a layer containing a cellulose ether.

Signed at Rochester, New York, this 17th day of February 1921.4

STEWART J. CARROLL. 

